Vacuum breaker including check valve



May 18, 1965 P. J. DUCHIN VACUUM BREAKER INCLUDING CHECK VALVE 2 Sheets-Sheet 1 Filed Aug. 22, 1962 Paul J Due/fin INVENTOR.

MWM

y 8, 1965 P. J. DUCHIN 3,183,924

VACUUM BREAKER INCLUDING CHECK VALVE Filed Aug. 22, 1962 2 Sheets-Sheet 2 Paul J Due/2i INVENTOR.

United States Patent 3,183,924 VACUUM BREAKER INCLUDING CHECK VALVE Paul J. Duchin, Milford, Mich, assignor to Aquaval Specialties, Inc., Milford, Mich, a corporation of Michigan Filed Aug. 22, 1962, Ser. No. 218,625 Claims. (Cl. 137-218) The present invention generally relates to means for preventing the back siphonage and backfiow of water in a water supply system, particularly in conjunction with the use of a sanitary water supply wherein the return of water from the discharge end of the system could cause a contamination of the water supply.

The undesirable reversal of the normal flow of water in a water supply system generally results from either backfiow or back siphonage with backfiow resulting from the weight of the water per square inch of column being greater than the pressure per square inch attempting to support the column of water, and with back siphonage resulting from a complete failaure of the water pressure as occurs because of a break in the water supply main or because of a shutting off of the supply for repair or maintenance purposes resulting in a draining of the supply line at some upstream point thereby creating a vacuum condition at the discharge end.

Accordingly, one of the primary objects of the present invention is to provide a device equally capable of elfectively preventing both backflow and back siphonage during pressure failures while maintaining a smooth and consistent flow at all other times.

Another object of the present invention resides in the provision of .such a device wherein the desired results are effected by the use of only a single check valve and sealing ring combination.

A further object of the present invention is to provide a vacuum breaker having few moving parts and being capable of use over extended periods of time with little or no maintenance being required.

Likewise, an object of the present invention resides in the simplicity of construction with any necessary repairs or replacements being accomplished without the necessity 'of completely disassembling the entire device.

These together with other objects and advantages which will become subsequently apparent reside in the details 'of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

FIGURE 1 is a perspective view of the vacuum breaker comprising the present invention;

FIGURE 2 is an enlarged cross-sectional view taken substantially on a plane passing along line 22 in FIG- URE 1;

FIGURE 3 is a cross-sectional view taken substantially on a plane passing along line 33 in FIGURE 2;

FIGURE 4 is a cross-sectional view taken substantially on a plane passing along line 4-4 in FIGURE 2; and

FIGURE 5 is an exploded perspective view of the various components comprising the vacuum breaker of the present invention.

Referring now more specifically to the drawings, reference numeral generally designates the vacuum breaker of the present invention. The vacuum breaker 10 includes a housing 12 formed of two sections 14- and 16 3,133,924 Patented May 18, 1965 water, thus acting as an inlet for the flow of Water through the breaker It). In order to provide an effective seal between the threaded faucet and the vacuum breaker 10, an annular washer 22 is provided at the forward end of the section 14 within an annular groove 24 with an enlarged washer seat or bulkhead 26 integrally formed with the section 14 and providing the forward limit of the annular groove 24.

a The forward section 15 of the housing 12 is provided with an externally threaded forward portion 28 for at tachment to suitable means such as a hose (not illus trated). This forward portion 28 terminates at its rear end in a laterally extending annular wall 30 which extends both outwardly and rearwardly. Secured to the outer end of the lateral wall 30 is a cylindrical wall 32 which terminates at its rear end in the aforementioned soldered joint 18 resulting in the formation of an enlarged rear chamber 34 and a reduced forward chamber 36 in the forward section 16.

An 0 type ring seal 38 is located within the rear chamber 34 and is of a size so as to peripherally engage the inner walls of the chamber 34- while at the same time being slidable relative thereto for movement between a first position in engagement with the forward face of the bulkhead 26 and a second position in engagement with an annular sealing seat 40 and the lateral wall 30 so as to effect a positive sealing of the oircumferentially spaced plurality of air ports 42 provided through the lateral wall 30.. It will of course be appreciated that the ring seal 38 is of a material capable of being slightly compressed so as to effect a positive seal with the rolling seating action of the '0 ring with the air port seat providing a water tight seal while preventing a cutting of the ring.

Slidably positioned within the forward chamber 36 is a check valve 44 consisting of a cylindrical upper portion 46 having a rounded closed top 48 and a rectangular lower section 50 of a length and width substantially equal to the diameter of the upper portion 4-6. The lower rectangular section 5t is provided with four forwardly extending corner legs 52 having bevelled outer edges 54 in sliding engaging with the inner wall of the forward chamber 36. It will be appreciated that such an arrangement provides for four through passages between the sides of the rectangular lower portion 50 and the inner walls of the cylindrical chamber 36.

As will be noted in FIGURE 2, the inner diameter of the sealing ring 38 is of a size so as to slidably engage the outer wall of the cylindrical upper portion 46 so as to effect a seal therebetween.

As will also be appreciated from FIGURE 2, the check valve 44 is provided with a forwardly opening inner tapered bore so as to enable the insertion therein of a coil spring biasing means 56, the rearward end of which is in engagement with the inner face of the top 48 of the check valve 44 and the forward end of which is in engagement with a spring seat 58 located within an interior annular groove 6h and retained in position by a retaining ring 62 similarly located in an interior annular groove 64.

Returning now to the rearward section 14, attention is directed to the fact that a setscrew 66 is provided for locking the vacuum breaker to a faucet thus preventing any unauthorized removal. Also, a drain hole 68 is to be provided so as to enable the draining of any trapped water thus preventing any possible freezing damage.

:In operation, the inlet end of the vacum breaker 10 .is secured to a suitable source of water such as by threading the rearward section 14 on a water faucet. As the (water is introduced, the flow enters the rear of the chamber 34 where it engages the seal 38 and the top 48 of the check valve t t causing a forward movement of both the seal 38 and the check valve 4 4 while maintaining encasedthe watertight seal therebetween and also between the seal 38 and the inner wall of the chamber. While it will be appreciated that the biasing spring 56 tends to prevent any premature disengagement of the check valve from the sealing ring 38, it is also contemplated that the force receiving surface of the ring 3% be greater than the force receivingsurface of the check valve 44 so as provide an additional means for preventing this prema ture separation.

As the water pressure increases suificiently to overcome the combined force of the spring as and the frictional drag of the seal 33, the check valve 44 and seal 68 jointly move toward the sealing seat 4%. This joint movement of the check valve 4-4- and the sealing ring 38 is finally arrested when the ring 38 contacts the seat 40 at which time it is forced into sealing engagement in relation to the holes 42 through the lateral wall 3%, the check valve 44 continuing to move toward the forward or discharge end of the housing 12 so as to provide for a discharge of the water therethrough.

Should a stoppage of flow occur on the outlet side, such as a closure of a hose nozzle, the check valve 44 will immediately return to scaling contact with the seal 38 due to balanced pressures on both sides thereof and the biasing of the spring 56 with the biasing of the spring 56 not being sufiicient to overcome the pressure maintaining the seal .in contact with the apertured lateral wall 30 thus preventing both a reversal of the flow and leakage through the air ports 42.

If the inlet pressure is cut-off, such as by a closure of the faucet, flow through the vacuum breaker 10 ceases and the spring 56 returns the check valve 44- into sealing contact with the sealing ring 38, the check valve 44 and sealing ring 38 then being jointly urged rearwardly toward the bulkhead 26. Any subsequent backflowing of the water into the outlet end of the beaker it) would now merely ilow out of the air ports 42 thus preventing any contamination of the water supply.

In the event that a vacuum or negative pressure should occur within the pipes while the facuet spigot is in an open condition and a fouling of the check valve 4-4 occurs, it is contemplated that the combined area of the air ports be as large as or greater than the area of the outlet end of the breaker It) so as to enable the drawing in of a suiiicient amount of :air to eliminate the vacuum thus preventing any back siphoning of the contaminated water.

From the foregoing description taken in conjunction with the drawings, it is considered to be readily apparcut that a novel vacuum breaker has been defined which enables the flow of water in a straight path with a single ring seal providing an effective sealing with the check valve on its inner circumference and with the flow passage on its outer circumference, a high flow rate being possible due to clean passages provided by using an 0 ring which does not cause any undesirable deflection in the flow. Further, it will be appreciated that the specific arrangement of the ring seal, check valve, biasing means and retaining ring is such as to allow for their insertion into the housing 12 without disassembling the housing thus allowing for a permanent interconnection of the two sections 14- and 16 or in tact the use of a one-piece housing thereby eliminating the annoyance of parts becoming separated due to loose threads at the joint between the sections, or leaks due to poor seals. Likewise, if so desired, the vacuum breaker can be assembled within the discharge end of a conventional faucet upon a slight modification thereof thus providing a built in vacuum breaker. Also, the specific arrangement and relative size of the various elements is considered highly effective as a means for preventing any escape of flow through the air ports due to the manner in which the ports must be positively sealed before any discharge of :Water can OCCUI.

During periods of normal flow, the ring seal is in principles of the invention.

and, the check valve is urged forwardly so as to allow for the how between the ring seal and rounded end of the check valve. Upon a stoppage of the flow and the application of a low vacuum the biasing spring urges the valve rearward'ly int-o contact with the ring seal, this occurring while a low pressure still exists in the valve, which pressure is however in-suiiicient to overcome the spring load. As the pressure further drops to zero and as a vacuum is created, the ring seal and check valve move rearward'ly together urged by the bias ing spring and the vacuum until the air ports are uncovered with the spring seal and check valves at no time losing contact with each other either during or after the unseating of the ring seal from the seal seat, thus resulting in the positive preventing of any leaks even those due to the application of a low vacuum.

Another significant feature of the above described vacuum breaker resides in the fact that the provision of a substantial differential in the area of the ring seal and check valve top relative to the reduced discharge or outlet opening results in an effective prevention of the rearward movement of the ring seal due to a water hammer effect resulting from a rapid closure of a discharge nozzle which would otherwise cause an undesirable spraying of the water through the air ports.

As such, it is considered to .be readily apparent that a novel vacuum breaker has been defined supra wherein most if not all the deficiencies in the various known types of vacuum breakers are overcome in a simple though highly effective manner.

The foregoing is considered as illustrative only of the Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invent-ion as claimed.

What is claimed as new is as follows:

1. A vacuum breaker for a water supply system comprising a housing having communicating rearward inlet and forward outlet portions, said housing being substantially cylindrical with the rearward portion being larger in diameter than the forward portion, both portions defining interior surfaces, an annular lateral wall being provided between the adjacent inner ends of the rearward and forward portions, air intake means, said air intake means consisting of a plurality of air ports through said lateral wall, sealing means, said sealing means comprising a resilient ring seal located within the rearward portion adjacent the air intake ports and in peripheral slidable engagement with the interior surface thereof, said seal selectively completely sealing said air ports, slidably mounted check valve means, said check valve means cooperating with said seal for selectively preventting communication between the rearward inlet and forward outlet portions by forming a flow barrier rearward of the air intake ports, means normally biasing said check valve means int-o engagement with said seal, said check valve means being mounted for movement .both in conjunction with the seal for maintaining the flow barrier and relative to said seal for enabling flow therebetween, said lateral wall limiting the forward movement of said seal while allowing continued forward movement of the check valve means for enabling relative movement therebetween sufficient so as to allow a flow of fluid therethrough from the rearward inlet portion to the forward outlet portion.

2 A vacuum breaker for a water supply system comprising a one-piece housing having communicating rearward inlet and forward outlet portions, said housing being substantially cylindrical with the rearward portion being larger in diameter than the forward port-ion, both portions defining interior surfaces, an annular lateral wall being provided between the adjacent inner ends of the rearward and forward portions, air intake means, said air intake means consisting of a plurality of air ports through said lateral wall, sealing mean-s, said sealing means comprising a resilient ring seal located within the rearward portion adjacent the air intake ports and in peripheral slidable engagement with the interior surthe flow barrier .and relative to said seal for enabling lfiOW therebetween, said lateral wall limiting the forward movement of said seal while allowing continued forward movement of the check valve means for enabling relative movement therebetween sufiicient so as to allow a [How of fluid therethrough from the rearward inlet portion to the forward outlet portion.

3. The combination of claim 1 wherein said check valve includes a closed end cylindrical upper portion and a radially enlarged rectangular lower portion having four corners thereonv project-ing beyond said cylindrical upper portion, said corners being in slidable engagement with the interior surfiace ofthe forward portion, the cylindrical upper portion of the check valve being sealingly engageable with the inner surface of the ring seal.

4. The combination of claim 2 wherein said check valve includes a closed end cylindrical upper portion and a radially enlarged rectangular lower portion having the four corners thereon projecting beyond said cylindrical upper portion, said corners being in slidable engagement 'with the interior surface of the forward portion, the cylindrical upper portion of the check valve being sealingly engageable with the inner surfiace of the ring seal.

5. The combination of claim ,1 wherein said check valve includes a closed end cylindrical upper portion and a radially enlarged polygonal lower portion having corners thereon projecting beyond said cylindrical portion, said corners being in slidable engagement with the interior surface of the iorward portion, the cylindrical upper portion of the check valve being sealingly engageab'le with the inner surface of the ring seal.

References Cited by the Examiner UNITED STATES PATENTS 214,719 4/79 Sherboudy 137512.2 2,259,984 10/41 Anderson 137217 XR 2,941,541 6/60 Peras l37-l02 2,960,996 11/60 Hazelton 137-218 XR 3,023,767 3/62 Woodford 1372 18 3,065,761 11/62 Peras 137-.-102.

v FOREIGN PATENTS 839,642 6/60 Great Britain.

ISADOR WEIL, Primary Examiner.

WILLIAM F. O-DEA, Examiner. 

1. A VACUUM BREAKER FOR A WATER SUPPLY SYSTEM COMPRISING A HOUSING HAVING COMMUNICATING REARWARD INLET AND FORWARD OUTLET PORTIONS, SAID HOUSING BEING SUBSTANTIALLY CYLINDRICAL WITH THE REARWARD PORTION BEING LARGER IN DIAMETER THAN THE FORWARD PORTION, BOTH PORTIONS DEFINING INTERIOR SURFACES, AN ANNULAR LATERAL WALL BEING PROVIDED BETWEEN THE ADJACENT INNER ENDS OF THE REARWARD AND FORWARD PORTIONS, AIR INTAKE MEANS, SAID AIR INTAKE MEANS CONSISTING OF A PLURALITY OF AIR PORTS THROUGH SAID LATERAL WALL, SEALING MEANS, SAID SEALING MEANS COMPRISING A RESILIENT RING SEAL LOCATED WITHIN THE REARWARD PORTION ADJACENT THE AIR INTAKE PORTS AND IN PERIPHERAL SLIDABLE ENGAGEMENT WITH THE INTERIOR SURFACE THEREOF, SAID SEAL SELECTIVELY COMPLETELY SEALING SAID AIR PORTS, SLIDABLY MOUNTED CHECK VALVE MEANS, SAID CHECK VALVE MEANS COOPERATING WITH SAID SEAL FOR SELECTIVELY PREVENTING COMMUNICATION BETWEEN THE REARWARD INLET AND FORWARD OUTLET PORTIONS BY FORMING A FLOW BARRIER REARWARD OF THE AIR INTAKE PORTS, MEANS NORMALLY BIASING SAID CHECK VALVE MEANS INTO ENGAGEMENT WITH SAID SEAL, SAID CHECK VALVE MEANS BEING MOUNTED FOR MOVEMENT BOTH IN CONJUNCTION WITH THE SEAL FOR MAINTAINING THE FLOW BARRIER AND RELATIVE TO SAID SEAL FOR ENABLING FLOW THEREBETWEEN, SAID LATERAL WALL LIMITING THE FORWARD MOVEMENT OF SAID SEAL WHILE ALLOWING CONTINUED FORWARD MOVEMENT OF THE CHECK VALVE MEANS FOR ENABLING RELATIVE MOVEMENT THEREBETWEEN SUFFICIENT SO AS TO ALLOW A FLOW OF FLUID THERETHROUGH FROM THE REARWARD INLET PORTION TO THE FORWARD OUTLET PORTION. 